SHURE AM8T
Owner's Manual

Model AM8T User Guide
GENERAL DESCRIPTION
The AM8T handheld, amplified, noise-canceling DTMF communications microphone is FAA Certified for aircraft application (TSOC58a). In addition to its extremely clear transmission, even in noisy environments, the AM8T has very low sensitivity to hum pickup and low susceptibility to radio frequency interference. Audio and DTMF levels can be independently adjusted with the supplied screwdriver to match the transmitter input gain. These protected external controls prevent accidental changes by the user while allowing adjustments without having to disassemble the microphone case. The microphone has an illuminated keypad made of tough silicone rubber, with durable printed characters that will last the life of the microphone. The keypad is backlit by red LEDs, easily visible during night operation, minimizing eye readjustment for night vision. The AM8T is designed for use with most currently available aircraft radios. For convenience, all microphone and signaling functions, including keypad illumination, are powered directly from the microphone input circuit of most transmitters, reducing the need for separately) connects the modular telephone-type socket of the equipment modification. A five-conductor MODULINK® cable (sold

FEATURES � FAA CERTIFIED FOR AIRCRAFT USE � DETACHABLE MODULINK® MODULAR PLUG COIL CORD � � � � � � � � � �
WITH PJ-068 AIRCRAFT-RADIO PLUG OR A4M TYPE CONNECTOR NOISE-CANCELING WITH FREQUENCY RESPONSE TAILORED FOR OPTIMUM INTELLIGIBILITY TOP-TALK SOUND CHANNEL� FOR CLEAR VOICE INPUT, EASY HANDLING BUILT-IN TRANSISTOR AMPLIFIER POWERED BY CARBON-MICROPHONE-TYPE CIRCUIT ILLUMINATED KEYPAD WITH POSITIVE TACTILE CONFIRMATION AND AUDIBLE VERIFICATION TONES SIMPLE EASY-TO-USE CONTINUOUS-TONE DIALING SCREWDRIVER ACCESSIBLE DTMF LEVEL ADJUSTMENT, INDEPENDENT OF MICROPHONE GAIN SETTING LOW SENSITIVITY TO HUM AND RF INTERFERENCE RUGGED MILLION-CYCLE PLUS� LEAF-TYPE SWITCH STANDS UP UNDER SEVERE ENVIRONMENTS AND CONSTANT USE HIGH IMPACT ARMO-DUR® CASE, STRONG, LIGHTWEIGHT, COMFORTABLE TO THE TOUCH IN HOT OR COLD ENVIRONMENTS RUGGED AND DEPENDABLE UNDER ALL OPERATING CONDITIONS

AM8T to most aircraft radios using a PJ-068 plug. This cable can be instantly changed or replaced without soldering. The AM8T is ergonomical, fitting naturally and comfortably in the hand. The voice-entry port is at the top of the microphone body for simple, natural transmitting. The microphone is not affected by heat or humidity, and the rugged ARMO-DUR® case is immune to oil, grease, most fumes and solvents, salt spray, sun, rust and corrosion. The AM8T is outstanding in its ability to withstand mechanical shocks and vibration. Its Million-Cycle Plus� leaf-type switch is a double-pole, single-throw type that resists the effects of severe operating conditions and constant use. It has nickel-silver blades with palladium alloy contacts for reliable oxidation-free operation. The microphone is supplied with output levels factory preset to meet TSO-C58a requirements. Adjustments should be made only by an FAA Approved Service Facility or the Shure Service Department. The AM8T is supplied with a small screwdriver for releasing the modular-plug microphone cable from the case and for adjusting the microphone amplifier gain and DTMF level. A nickel-plated steel mounting bracket is included for mounting on or near radio equipment.

SET-UP
The AM8T is equipped with a rear-case hang-up button for use with a mounting bracket on associated equipment.

CONNECTIONS
To attach the cable to the AM8T, insert the modular telephonetype plug in the microphone jack until it locks. To remove the cable from the microphone, unlock the plug by inserting the small screwdriver supplied with the AM8T in case hole �A� just above the cable jack (see Figure 4). Microphone connector wiring is shown in the table below. The ALM-88 cable is wired at the microphone connector as shown in Figure 3.
Table 1. Microphone Connector Wiring Pin Color 1 Function N.C. Pin 5 Color Function Black PTT Switch Ground Audio Out (Ac coupled) Ground N.C.

PART OF A COMPLETE LINE
The 598T is part of a full line of mobile microphones, circuitry products and related accessories. For a complete listing, contact your Shure Representative or visit www.shure.com.

2

White

Dc Bias (+), Audio Out

6

Red

3 4

Yellow PTT Switch Blue NC

7 8

Drain

APPLICATIONS � Aerospace
©2004, Shure Incorporated 27A6005B (Rev. 2)

®Shure, MODULINK, and ARMO-DUR are registered trademarks of Shure, Incorporated.� Million-Cycle Plus and Top-talk Sound Channel are trademarks of Shure Incorporated. All other trademarks are the property of their respective owners.

Printed in U.S.A.